It hasn't been starting too well when cold for some months, and really struggles to idle until i rev it for a while. Interestingly on the morning that it overheated it started pretty much instantly; thought it was my lucky day however i see now that was not the case!

 

Thanks for the reply, will try get my hands on the equipment to test.

Usually the water vapour that leaks into a cylinder as the motor cools gets onto the spark plug and it doesn't fire very well in the morning. Once its up and running it starts fine for the rest of the day, until it cools down overnight again.